Optimising costs in data centres is a constant, significant challenge for today’s IT managers, says Rittal’s Clive Partridge. Benefitting from the free cooling available from nature is clearly a wise option. Energy usage is one of those costs to be optimised, particularly the energy required to for the technology used to cool computer servers. Some very high-tech equipment has been developed in recent years which has increased the efficiency of coolers. However, it’s also worth noting that natural sources of cooling can also be considered, including cold water and cool ambient air. So, if this is a route you’re considering, what questions what do you need to ask to get started?